There is a need for a wide field-of-view compound eye optics for semi-active laser (SAL) spot-tracking missile seekers to provide precision guidance to targets, for illuminated image tracking, and for image sensing, all in the presence of elevated background illumination. An ideal device to meet these needs would provide a wide field of view (>10° cone angle) without the need for moving parts. The device would include spectral and angle filtering in the optical portion, plus electrical noise reduction. The background illumination could include the sun in the FOV and within 1° of the target. The illumination could, for example, be a near-infrared (NIR), repetitively pulsed laser. The device would produce an electronic signal to enable a tracking system to follow the target. Such a signal could, for example, be a simple set of voltages or digital data, indicating whether or not the target is centered in the FOV of the device and, if it is not centered, indicating the direction off center where the target is located.
Current SAL seekers, for example, use single aperture optics and suffer from a limited FOV (about 10°), which is insufficient to search for and acquire the target. The seekers also suffer from relatively high ambient noise, both electronically and in the optical portion; they are therefore inefficient in blocking bright sunlight. Illuminated image-tracking and -sensing devices suffer from the same difficulties.